Undefined Python references in g++

Question

I am using the following command:

g++ -L/usr/lib/panda3d -L/usr/lib -o "panda3dplayground"  ./main.o   -lpython2.7 -lp3pystub -lp3framework -lpandafx -lp3pystub -lpandaexpress -lpanda -lp3framework -lp3direct

And I am getting the following errors:

/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Cmp'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyUnicodeUCS4_FromWideChar'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_SetItem'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_ValueError'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_SetItemString'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyType_IsSubtype'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyString_FromString'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Fetch'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_StandardError'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyInt_AsSsize_t'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyArg_Parse'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyEval_RestoreThread'
/usr/lib/panda3d/libpandaexpress.so: undefined reference to `PyString_AsStringAndSize'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_CallFunction'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_Size'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyString_Size'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Print'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_SetString'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyGILState_Ensure'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_CallObject'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyString_FromStringAndSize'
/usr/lib/panda3d/libp3dtool.so: undefined reference to `PySys_GetObject'
/usr/lib/panda3d/libp3dtool.so: undefined reference to `PyList_GetItem'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_AssertionError'
/usr/lib/panda3d/libp3dtoolconfig.so: undefined reference to `Py_InitModule4_64'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyModule_AddStringConstant'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyGen_Type'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Compare'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyList_Append'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyMapping_GetItemString'
/usr/lib/panda3d/libp3dtoolconfig.so: undefined reference to `PyArg_ParseTuple'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyTuple_Pack'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyLong_FromUnsignedLongLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Repr'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyInt_FromLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyArg_ParseTupleAndKeywords'
/usr/lib/panda3d/libpanda.so: undefined reference to `_Py_NoneStruct'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyList_SetItem'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyCallable_Check'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Clear'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyLong_AsUnsignedLongLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_ExceptionMatches'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_New'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyUnicodeUCS4_AsWideChar'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyInt_AsLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyUnicodeUCS4_GetSize'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_RichCompareBool'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyModule_AddObject'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyGILState_Release'
/usr/lib/panda3d/libpanda.so: undefined reference to `PySequence_GetItem'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyLong_AsUnsignedLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `_Py_NotImplementedStruct'
/usr/lib/panda3d/libpanda.so: undefined reference to `PySequence_Size'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_TypeError'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyNumber_Long'
/usr/lib/panda3d/libpanda.so: undefined reference to `Py_BuildValue'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyEval_InitThreads'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyType_Ready'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyFloat_FromDouble'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_GenericSetAttr'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_IsTrue'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyImport_GetModuleDict'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Free'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyNumber_Float'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyBool_FromLong'
/usr/lib/panda3d/libp3dtoolconfig.so: undefined reference to `PyLong_AsLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_IndexError'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyLong_AsLongLong'
/usr/lib/panda3d/libpandaexpress.so: undefined reference to `PyLong_FromLongLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyFloat_AsDouble'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyEval_SaveThread'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Restore'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_WarnEx'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyString_Type'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_StopIteration'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Type'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_Call'
/usr/lib/panda3d/libpanda.so: undefined reference to `PySequence_Check'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyType_GenericAlloc'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyString_AsString'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyModule_AddIntConstant'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_CallMethod'
/usr/lib/panda3d/libp3dtool.so: undefined reference to `Py_IsInitialized'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_GetAttrString'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyList_New'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_SystemExit'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_GetItem'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_FutureWarning'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyTuple_New'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Format'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyCFunction_NewEx'
/usr/lib/panda3d/libp3dtoolconfig.so: undefined reference to `PyLong_FromUnsignedLong'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyExc_AttributeError'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyObject_GenericGetAttr'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyTuple_Size'
/usr/lib/panda3d/libpanda.so: undefined reference to `PySequence_Fast'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyErr_Occurred'
/usr/lib/panda3d/libpanda.so: undefined reference to `PySequence_Tuple'
/usr/lib/panda3d/libpanda.so: undefined reference to `PyDict_DelItemString'
collect2: error: ld returned 1 exit status

Why isn't g++ recognizing libpython2.7.so? I checked out and it is located in /usr/lib.

Link order matters. Move `-lpython2.7` so that it appears _after_ all the libraries that are missing some of its functions. — Mat, May 05 '13 at 07:43
Check that the architecture of `libpython` (x86/x64) matches that of the rest of your program — n. m. could be an AI, May 05 '13 at 07:45
@Mat Thanks! That worked. Post it as an answer and make a brief explanation and I will post it as correct — Pacha, May 05 '13 at 07:56
I've already answered "this question" a few times (e.g. [here](http://stackoverflow.com/a/10001085/635608) or [here](http://stackoverflow.com/a/7330127/635608).) Can't really close as dup since it's not exactly the same thing but it's the same underlying problem. Feel free to post the exact steps you took to fix it as an answer to your own question though. — Mat, May 05 '13 at 08:01

Employed Russian · Accepted Answer · 2020-10-06T14:53:32.020

7

The order of libraries on the link line matters, and your order is wrong.

edited Oct 06 '20 at 14:53

answered May 05 '13 at 16:34

Employed Russian

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Hyperlink is broken, please fix. – tripulse Oct 06 '20 at 11:38
@tripulse Fixed. – Employed Russian Oct 06 '20 at 14:53

Undefined Python references in g++

1 Answers1

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